Improvement in blackboard-rubbers



VAla. HuRToN.

Black-Board Rubbers.

Vit nessus UNITED STATES.

PA'IEN'rm OFFICE."

PEMBRTON B. HORTON, OF SAN FRANCISCO, CALIFORNIA.

IMPROVEMENT IN BuioKBOARD-RUBBERS.. i

Specification forming part of Letters Patent No. l 44,674, dated Nev( mber 18, 1873 application filed 1 June :21, 1872.

To all whom it may concern:

Be it known that I, PEMBERTON B. HOR- TON, of city and county of San Francisco, State of California, have invented an Improved Blackboard-Rubber; and I do hereby declare the following description and accompanying drawings are sufficient to enable any person skilled in the art Or science. to which it most nearly appertains to make and use my said invention or improvement without further in vention or experiment.

My invention relates to an improved brush or rubber for removing chalk-marks from blackboards.

My improvement consists in the employment of several thicknesses of felt, secured to a flex- -ible backing, for providing a soft and yielding surface for rubbing against the blackboard for removing the marks.

In order to more fully describe my blackboard-rubber, reference is had to the accompanying drawing forming a part of this specification, in which a perspective of the brush is shown.

A is a back, which can be made of any suitable elastic Or suitable material, although I prefer leather or pasteboard. A strap, b, is properly secured across the back tO provide a handle for holding the rubber. The rubbing surface consists of one or more thicknesses of felt, c, which are secured to the back by means of a suitable glue or cement. Usually, I shall use a Water-proof cement or glue.

This felt surface will be soft and yielding and very durable, While a rubber can be posed Of one or more thicknesses of felt, c, se- A cured to a leather or other flexible backing, A, substantially as specified.

In Witness whereof I hereunto set my hand and seal.

PEMBERTON B. HOBTON. [L s.] Witnesses:

J. L. BOONE, C. M. RICHARDSON. 

